1. Field Of The Invention
The present invention relates to an electromagnetic flow meter and more particularly to an electromagnetic flow meter wherein a signal-to-noise (S/N) ratio is improved.
2. Description Of The Prior Art
In order to increase an electromotive force between detecting electrodes of the electromagnetic flow meter without increasing the density of magnetic flux applied to the flow meter, the following method has been adopted in the prior art flow meter of this kind. Namely, a plurality of electrode pairs are arranged along the wall of a fluid flow pipe along the axis of the same, and electromotive forces obtained by respective electrode pairs are composed, or summed, to establish an increased electromotive force of the detecting electrode configuration. According to the prior art flow meter of this kind, however, it is often observed that the electromotive forces of the electrode pairs are different from each other which creates a summing conflict. Further, there is another disadvantage in that the input terminal, and the leads of a converter, which is a circuit for composing the electrode signals, are apt to pick up external noise signals. Therefore, various kinds of complicated matching circuits are needed to overcome such disadvantages.